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<a name="boost_multiprecision.tut.rational.rational_adaptor"></a><a class="link" href="rational_adaptor.html" title="rational_adaptor">rational_adaptor</a>
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<pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">multiprecision</span><span class="special">{</span>

<span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">IntBackend</span><span class="special">&gt;</span>
<span class="keyword">class</span> <span class="identifier">rational_adpater</span><span class="special">;</span>

<span class="special">}}</span>
</pre>
<p>
          The class template <code class="computeroutput"><span class="identifier">rational_adaptor</span></code>
          is a back-end for <code class="computeroutput"><span class="identifier">number</span></code>
          which converts any existing integer back-end into a rational-number back-end.
        </p>
<p>
          So for example, given an integer back-end type <code class="computeroutput"><span class="identifier">MyIntegerBackend</span></code>,
          the use would be something like:
        </p>
<pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">number</span><span class="special">&lt;</span><span class="identifier">MyIntegerBackend</span><span class="special">&gt;</span>                    <span class="identifier">MyInt</span><span class="special">;</span>
<span class="keyword">typedef</span> <span class="identifier">number</span><span class="special">&lt;</span><span class="identifier">rational_adaptor</span><span class="special">&lt;</span><span class="identifier">MyIntegerBackend</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">MyRational</span><span class="special">;</span>

<span class="identifier">MyRational</span> <span class="identifier">r</span> <span class="special">=</span> <span class="number">2</span><span class="special">;</span>
<span class="identifier">r</span> <span class="special">/=</span> <span class="number">3</span><span class="special">;</span>
<span class="identifier">MyInt</span> <span class="identifier">i</span> <span class="special">=</span> <span class="identifier">numerator</span><span class="special">(</span><span class="identifier">r</span><span class="special">);</span>
<span class="identifier">assert</span><span class="special">(</span><span class="identifier">i</span> <span class="special">==</span> <span class="number">2</span><span class="special">);</span>
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<td align="right"><div class="copyright-footer">Copyright © 2002-2020 John
      Maddock and Christopher Kormanyos<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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